How Many Processor Cores Are Enough?
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From: Terje Mathisen on 2 Oct 2006 04:21 jsavard(a)ecn.ab.ca wrote: > Once you've done just about as well as you can in these areas, about > the only reasonable-cost avenue you have *left* for improving > performance is to include more processor cores in your design. I agree. > > This is where the microcomputer revolution has ended up at present - > where it's almost impossible to design a "supercomputer" that has > better single-thread performance than your desktop PC. Not totally > impossible, though; there is room to get ahead of that curve a little > bit - the Itanium is proof of that, for example. Except that the Itanium doesn't really outperform 'standard' PC cpus on SpecInt, only on FP stuff, and barely there as well. Price/performance is not good at all, unfortunately. Terje -- - <Terje.Mathisen(a)hda.hydro.com> "almost all programming can be viewed as an exercise in caching"
From: Bernd Paysan on 2 Oct 2006 08:19 jsavard(a)ecn.ab.ca wrote: > Israel, like Denmark and the United States, is a democratic country of > happy, peaceful people. Oh, man. I'm all for Denmark in this statement, since they are really quite democratic and peaceful, despite of the Mohammed cartoons. But the USA as a state are not so peaceful. During the cold war, the USA developed a habit of attacking other contries without being substantial threatened by them (e.g. the Vietnam war started, because two US soldiers were killed). A few years ago, they illegally attacked Irak, and brought a lot more terror to the world in the attempt to fight fire with oil. Israel is not so peaceful, either. The founder of that country, Ben Gurion, was a terrorist before. It is not so democratic, as well. Many presidents were generals in the military before (apparently, the current leadership is a rare exception); a democratically legitimized military government, mostly. A few month ago, Israel illegally invaded Lebanon, to avenge the kidnapping of two soldiers by Hesbollah (which by itself was to avenge the kidnapping of half the palestinean government by Israel, an avenge to kidnapping of one soldier by Hamas... sounds like a typical vendetta where someone soon will bring up the still pending issue of David vs. Goliath, as well ;-). -- Bernd Paysan "If you want it done right, you have to do it yourself" http://www.jwdt.com/~paysan/
From: Dennis M. O'Connor on 2 Oct 2006 09:55 "Bernd Paysan" <bernd.paysan(a)gmx.de> wrote ... > (e.g. the Vietnam war started, because two US soldiers were killed) Not hardly. Where did you learn something so ridiculous ? The most probable cause of the Vietnam War was that US, during the Eisenhower and Kennedy administrations, refused to allow Vietnam, divided in 1954 by the treaty with France on a supposedly temporary basis, to re-unite peacefully. Now, please continue all these discussions in a more appropriate newsgroup. Thank you. -- Dennis M. O'Connor dmoc(a)primenet.com
From: Jon Forrest on 2 Oct 2006 11:47 jsavard(a)ecn.ab.ca wrote: > > I think you're asking the wrong question. > > For some purposes, the point of diminishing returns is at "two". > > So does that automatically mean that multi-core designs are a bad idea? Nobody said anything about multi-core being a bad idea. > Once you've done just about as well as you can in these areas, about > the only reasonable-cost avenue you have *left* for improving > performance is to include more processor cores in your design. But, if this too doesn't do much to improve performance, what's the point? Remember the Myth of Sisyphus? If increased clock speed, multi-cores, and all the other tricks don't result in better performance and/or lower cost then maybe it's time to look elsewhere, or maybe we've hit a wall imposed by human limitations, not technological. I worked in the CS Dept. at UC Berkeley during the middle and end of the Great Systems Era. Back then there was a huge need for increased hardware power. Now the emphasis seems to be on small systems, like sensors and nano-tech, where single system compute power isn't all that important. Of course, there are exceptions, but the trend is clear. Jon Forrest
From: Jon Forrest on 2 Oct 2006 11:54
rohit.nadig(a)gmail.com wrote: > The list is endless. I can see how every one of these applications is > ATLEAST 1 thread, if not more. These "daemons" can run on one computer > or many. But they will all have to communicate, manage data, and be > secure (think encrypted communication). The thing to keep in mind when thinking about future applications is how much faster they would run if you had a computer that has an infinite amount of computing power. In your example, and most of the others I've seen, this would make just a slight improvement. In your examples, most of the time you're network bound. Some of your video needs might be a little taxing but many of them can be done just fine today with a modern video card. Maybe another way to describe your problem is that you're software bound, not because the software runs too slowly but because it hasn't been written yet in a way that lets you comfortably and reliably do what you want. Jon Forrest |